Easy way to check that a variable is defined in python? [duplicate]

2024/11/20 14:19:00

Is there any way to check if a variable (class member or standalone) with specified name is defined? Example:

if "myVar" in myObject.__dict__ : # not an easy wayprint myObject.myVar
elseprint "not defined"
Answer

A compact way:

print myObject.myVar if hasattr(myObject, 'myVar') else 'not defined'

htw's way is more Pythonic, though.

hasattr() is different from x in y.__dict__, though: hasattr() takes inherited class attributes into account, as well as dynamic ones returned from __getattr__, whereas y.__dict__ only contains those objects that are attributes of the y instance.

https://en.xdnf.cn/q/26314.html

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